scholarly journals The importance and movement of mud bacterial carbon within the symbiosis of the New Zealand sea anemone Anthopleura aureoradiata

2021 ◽  
Author(s):  
◽  
Andrew Cornwall
Keyword(s):  
Organic Carbon ◽  
Protein Content ◽  
Starch Content ◽  
Light Availability ◽  
Host Protein ◽  
Natural Diet ◽  
Symbiotic Algae ◽  
Planktonic Food ◽  
Host Anemone ◽  
Reduced Rate

<p>A. aureoradiata is New Zealand’s only native cnidarian to form a phototrophic symbiosis with dinoflagellate microalgae. It is of particular interest as it can be found in estuarine mudflat habitats attached to cockles, where it spends a portion of the day submerged under the mud, either partially or completely. This scenario is very different to the situation in the tropics, where comparable symbioses (e.g. those with reef-building corals) live in brightly lit, clear waters. How A. aureoradiata maintains a stable symbiosis is therefore of considerable interest, with one potential mechanism involving the acquisition of carbon from the surrounding mud to counter the reduced availability of light and hence the reduced rate of photosynthesis.  In this thesis, I established the extent to which organic carbon in mud (especially bacteria) can be assimilated by A. aureoradiata and to what extent, if any, this carbon contributes to symbiosis nutrition and facilitates symbiosis stability under otherwise sub-optimal conditions. In the first instance, anemones were given access to¹³C glucose-labelled mud for 12 hours, in both the light and dark, and the extent of label incorporation (¹³C enrichment) in both the host and symbiont was measured by mass spectrometry. Subsequently, A. aureoradiata was starved of planktonic food for six weeks in the presence of differing quantities of unlabelled mud (‘no-mud’, ‘low-mud’ and ‘high-mud’), either with or without light, and a range of nutritional and biomass parameters measured. These included symbiont density, host protein content, and the accumulation of host lipid and symbiont starch stores.  Both the host anemone and its symbiotic algae showed signs of ¹³C uptake from the mud. Host anemones maintained in the dark assimilated more ¹³C label from the mud than did anemones incubated in the light, while the extent of label assimilation by the symbionts was unaffected by irradiance. Enhanced heterotrophic feeding in the dark is consistent with patterns reported for other symbiotic cnidarians, such as reef corals, where the host must counter the reduced availability of photosynthate from the symbiotic algae. However, the reason for the equal labelling of the symbionts in the light and dark is less clear. Nevertheless, factors such as reverse translocation in the dark (i.e. the transfer of organic carbon from host to symbiont), dark fixation of inorganic carbon, and a higher respiration rate of symbionts in the light than dark, could act either alone or in concert to produce the labelling pattern seen.  While the host and symbiont showed evidence of carbon uptake from the surrounding mud, mud quantity had no effect on either the host’s or symbiont’s storage products (% of starch in symbiont biomass, host protein content and lipid content), or on symbiont density. The lack of an effect of mud suggests that mud-derived bacteria comprise little of the host’s natural diet. In contrast, increased light availability (independent of mud availability) did lead to elevated symbiont density and symbiont starch content, consistent with the phototrophic nature of this symbiosis. More surprising was that host protein content was highest in the dark, suggesting perhaps that the symbionts were less of an energetic drain on their host when starved in the dark due to their lower population density.  In summary, my thesis provides evidence that A. aureoradiata and its symbiotic algae can use organic carbon obtained from the surrounding mud for their nutrition, but that this carbon source is of only negligible importance. These results are consistent with previous findings for the uptake and role of mud-derived nitrogen in this system. Further work to establish how this symbiosis maintains its remarkable stability under apparently sub-optimal, low-light conditions is therefore needed.</p>

scholarly journals The importance and movement of mud bacterial carbon within the symbiosis of the New Zealand sea anemone Anthopleura aureoradiata

2021 ◽  
Author(s):  
◽  
Andrew Cornwall
Keyword(s):  
Organic Carbon ◽  
Protein Content ◽  
Starch Content ◽  
Light Availability ◽  
Host Protein ◽  
Natural Diet ◽  
Symbiotic Algae ◽  
Planktonic Food ◽  
Host Anemone ◽  
Reduced Rate

<p>A. aureoradiata is New Zealand’s only native cnidarian to form a phototrophic symbiosis with dinoflagellate microalgae. It is of particular interest as it can be found in estuarine mudflat habitats attached to cockles, where it spends a portion of the day submerged under the mud, either partially or completely. This scenario is very different to the situation in the tropics, where comparable symbioses (e.g. those with reef-building corals) live in brightly lit, clear waters. How A. aureoradiata maintains a stable symbiosis is therefore of considerable interest, with one potential mechanism involving the acquisition of carbon from the surrounding mud to counter the reduced availability of light and hence the reduced rate of photosynthesis.  In this thesis, I established the extent to which organic carbon in mud (especially bacteria) can be assimilated by A. aureoradiata and to what extent, if any, this carbon contributes to symbiosis nutrition and facilitates symbiosis stability under otherwise sub-optimal conditions. In the first instance, anemones were given access to¹³C glucose-labelled mud for 12 hours, in both the light and dark, and the extent of label incorporation (¹³C enrichment) in both the host and symbiont was measured by mass spectrometry. Subsequently, A. aureoradiata was starved of planktonic food for six weeks in the presence of differing quantities of unlabelled mud (‘no-mud’, ‘low-mud’ and ‘high-mud’), either with or without light, and a range of nutritional and biomass parameters measured. These included symbiont density, host protein content, and the accumulation of host lipid and symbiont starch stores.  Both the host anemone and its symbiotic algae showed signs of ¹³C uptake from the mud. Host anemones maintained in the dark assimilated more ¹³C label from the mud than did anemones incubated in the light, while the extent of label assimilation by the symbionts was unaffected by irradiance. Enhanced heterotrophic feeding in the dark is consistent with patterns reported for other symbiotic cnidarians, such as reef corals, where the host must counter the reduced availability of photosynthate from the symbiotic algae. However, the reason for the equal labelling of the symbionts in the light and dark is less clear. Nevertheless, factors such as reverse translocation in the dark (i.e. the transfer of organic carbon from host to symbiont), dark fixation of inorganic carbon, and a higher respiration rate of symbionts in the light than dark, could act either alone or in concert to produce the labelling pattern seen.  While the host and symbiont showed evidence of carbon uptake from the surrounding mud, mud quantity had no effect on either the host’s or symbiont’s storage products (% of starch in symbiont biomass, host protein content and lipid content), or on symbiont density. The lack of an effect of mud suggests that mud-derived bacteria comprise little of the host’s natural diet. In contrast, increased light availability (independent of mud availability) did lead to elevated symbiont density and symbiont starch content, consistent with the phototrophic nature of this symbiosis. More surprising was that host protein content was highest in the dark, suggesting perhaps that the symbionts were less of an energetic drain on their host when starved in the dark due to their lower population density.  In summary, my thesis provides evidence that A. aureoradiata and its symbiotic algae can use organic carbon obtained from the surrounding mud for their nutrition, but that this carbon source is of only negligible importance. These results are consistent with previous findings for the uptake and role of mud-derived nitrogen in this system. Further work to establish how this symbiosis maintains its remarkable stability under apparently sub-optimal, low-light conditions is therefore needed.</p>

scholarly journals Starch Production in Chlamydomonas reinhardtii through Supraoptimal Temperature in a Pilot-Scale Photobioreactor

Cells ◽  
2021 ◽  
Vol 10 (5) ◽  
pp. 1084
Author(s):  
Ivan N. Ivanov ◽  
Vilém Zachleder ◽  
Milada Vítová ◽  
Maria J. Barbosa ◽  
Kateřina Bišová
Keyword(s):  
Chlamydomonas Reinhardtii ◽  
Starch Content ◽  
Light Availability ◽  
Fold Increase ◽  
Pilot Scale ◽  
Temperature Treatment ◽  
Control Culture ◽  
Starch Accumulation ◽  
Cellular Division ◽  
Starch Production

An increase in temperature can have a profound effect on the cell cycle and cell division in green algae, whereas growth and the synthesis of energy storage compounds are less influenced. In Chlamydomonas reinhardtii, laboratory experiments have shown that exposure to a supraoptimal temperature (39 °C) causes a complete block of nuclear and cellular division accompanied by an increased accumulation of starch. In this work we explore the potential of supraoptimal temperature as a method to promote starch production in C. reinhardtii in a pilot-scale photobioreactor. The method was successfully applied and resulted in an almost 3-fold increase in the starch content of C. reinhardtii dry matter. Moreover, a maximum starch content at the supraoptimal temperature was reached within 1–2 days, compared with 5 days for the control culture at the optimal temperature (30 °C). Therefore, supraoptimal temperature treatment promotes rapid starch accumulation and suggests a viable alternative to other starch-inducing methods, such as nutrient depletion. Nevertheless, technical challenges, such as bioreactor design and light availability within the culture, still need to be dealt with.

scholarly journals Its What’s on the Inside That Counts: An Effective, Efficient, and Streamlined Method for Quantification of Octocoral Symbiodiniaceae and Chlorophyll

2021 ◽  
Vol 8 ◽  
Author(s):  
Rosemary Kate Steinberg ◽  
Emma L. Johnston ◽  
Teresa Bednarek ◽  
Katherine A. Dafforn ◽  
Tracy D. Ainsworth
Keyword(s):  
Protein Content ◽  
Surface Area ◽  
Water Movement ◽  
Chlorophyll Concentration ◽  
Dry Weight ◽  
Accurate Method ◽  
Host Protein ◽  
Biomass Composition ◽  
Wet Weight ◽  
Chlorophyll Concentrations

Ocean warming driven bleaching is one of the greatest threats to zooxanthellate cnidarians in the Anthropocene. Bleaching is the loss of Symbiodiniaceae, chlorophyll, or both from zooxanthellate animals. To quantify bleaching and recovery, standardised methods for quantification of Symbiodiniaceae and chlorophyll concentrations have been developed for reef-building scleractinian corals, but no such standard method has been developed for octocorals. For stony corals, quantification of Symbiodiniaceae and chlorophyll concentrations often relies on normalisation to skeletal surface area or unit of biomass [i.e., protein, ash-free dry weight (AFDW)]. Stiff octocorals do not change their volume, as such studies have used volume and surface area to standardise densities, but soft-bodied octocorals can alter their size using water movement within the animal; therefore, Symbiodiniaceae and chlorophyll cannot accurately be measured per unit of surface area and are instead measured in units of Symbiodiniaceae and chlorophyll per μg of host protein or AFDW. Though AFDW is more representative of the full biomass composition than host protein, AFDW is more time and resource intensive. Here, we provide a streamlined methodology to quantify Symbiodiniaceae density, chlorophyll concentration, and protein content in soft-bodied octocorals. This technique uses minimal equipment, does not require freeze-drying or burning samples to obtain ash weight, and is effective for down to 0.2 g wet tissue. Bulk samples can be centrifuged, the Symbiodiniaceae pellet washed, and the supernatant saved for protein analysis. This efficient technique allows for clean, easy to count samples of Symbiodiniaceae with minimal animal protein contamination. Chlorophyll a and c2 extractions occurs at different rates, with chlorophyll a taking 24 h to extract completely at 4°C and chlorophyll c2 taking 48 h. Finally, we found that where necessary, wet weight may be used as a proxy for protein content, but the correlation of protein and wet weight varies by species and protein should be used when possible. Overall, we have created a rapid and accurate method for quantification of bleaching markers in octocorals.

scholarly journals Effect of NPK fertilization on the yield and yield stability of different maize genotypes

2012 ◽  
pp. 101-104
Author(s):  
Ágnes Krivián ◽  
Mihály Sárvári
Keyword(s):  
Protein Content ◽  
Starch Content ◽  
N Fertilization ◽  
Quality Parameters ◽  
Dry Period ◽  
Sowing Time ◽  
Maize Genotypes ◽  
Grain Moisture ◽  
Long Term Experiment

The yielding capacity and quality parameters of 11 maize hybrids were studied in 2011 on calcareous chernozem soil in a 25-year long-term fertilization experiment in the control (without fertilization), in the base treatment of N 40 kg ha-1, P2O5 25 kg ha-1, K2O 30 kg ha-1 and in five treatments which were the multiplied doses of the base treatment. The N fertilizer was applied in the autumn and in the spring, while P and K fertilizers were applied in the autumn.The sowing time was 17–18 April, the time of harvest was 8 October. The 30-year average of precipitation (April–Sept) was 345.1 mm, the amount of precipitation did not differ greatly from that, however, its distribution was very unfavourable.It was found that the largest yield increment (as compared to the control) was in the treatment N 40 kg ha-1, P2O5 25 kg ha-1, K2O 30 kg ha-1 in the long-term experiment. The largest yields were obtained for the hybrids P9494, PR37N01 and PR35F38 (13.64–13.71 t ha-1). Due to the dry period at the end of the summer – beginning of autumn, the grain moisture content at harvest was favourably low, 12–18% depending on the treatment and the growing season. The N fertilization significantly increased the protein content of the kernel, but the starch content of the kernel decreased (significantly in several cases) with increasing fertilizer doses and yields as compared with the control.The highest protein content was measured in hybrids GK Boglár and Szegedi 386. The oil content was above 4% for GK Boglár, but the two hybrids were not among the best yielding hybrids in spite of their good inner content. The starch content was around 75 % without fertilization, it decreased with fertilization.For the tested hybrids, the fertilizer dose N 120 kg ha-1, P2O5 75 kg ha-1, K2O 90 kg ha-1 can be recommended with respect to efficacy and environmental considerations.

scholarly journals Monitoring the Impact of Electromagnetic Waves on Yield and Quality in Maize

2011 ◽  
Vol 68 (1) ◽  
Author(s):  
Florin IMBREA ◽  
Branko MARINCOVIC ◽  
Valeriu TABĂRĂ ◽  
PAUL PÎRŞAN ◽  
Gheorghe DAVID ◽  
...  
Keyword(s):  
Protein Content ◽  
Quality Indicators ◽  
Electromagnetic Waves ◽  
Starch Content ◽  
New Technology ◽  
Low Frequency ◽  
Cultivation Method ◽  
Yield And Quality ◽  
The Impact ◽  
Starch Yield

Experimenting new technology of cultivating maize is an important step forward in order to optimise the yielding capacity if a crop that ranks second among crops cultivated worldwide and first among crops cultivated in Romania. Using low frequency radiations to stimulate yield and quality in maize allows increases in yield between 10 and 15% compared to the classical cultivation method and an improvement of the quality indicators (protein content increased with 6-11% determining an increase of the protein yield per ha; starch content increased with 7-14%, which also determined an increase of the starch yield per ha; while fat content, another indicator we monitored, increased with 2-6%).

Nitrogen recycling or nitrogen conservation in an alga-invertebrate symbiosis?

1998 ◽  
Vol 201 (16) ◽  
pp. 2445-2453 ◽  
Author(s):  
J Wang ◽  
AE Douglas
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Organic Carbon ◽  
Ammonium Assimilation ◽  
Ammonium Concentration ◽  
Nitrogen Recycling ◽  
Symbiotic Algae ◽  
Carbon Compounds ◽  
Ammonium Production ◽  
Nitrogen Conservation

When corals and allied animals are deprived of their symbiotic algae, the ammonium content in their tissues rises. This is commonly interpreted as evidence for nitrogen recycling (i.e. algal assimilation of animal waste ammonium into amino acids that are released back to the animal), but it can also be explained as nitrogen conservation by the animal (i.e. reduced net ammonium production in response to the receipt of algal photosynthetic carbon). This study discriminated between these interpretations in two ways. First, the increased ammonium concentration in the sea anemone Aiptasia pulchella, caused by darkness or depletion of the alga Symbiodinium, was partially or completely reversed by supplementing the medium with organic carbon compounds (e.g. &lt;IMG src="/images/symbols/&agr ;.gif" WIDTH="9" HEIGHT="12" ALIGN= "BOTTOM" NATURALSIZEFLAG="3"&gt;-ketoglutarate). Second, the activity of the ammonium-assimilating enzyme glutamine synthetase and the concentration of protein amino acids in the free amino acid pool of the animal, which were depressed by darkness and algal depletion, were restored by exogenous carbon compounds. It is concluded that organic carbon, whether derived from algal photosynthate or exogenously, promotes the animal's capacity for ammonium assimilation and reduces ammonium production from amino acid degradation. These processes contribute to nitrogen conservation in the animal, but they confound the interpretation of various studies on nitrogen recycling by symbiotic algae.

Effect of sowing date on the yield and quality of maize hybrids with different growing seasons

2009 ◽  
Vol 57 (4) ◽  
pp. 389-399 ◽  
Author(s):  
J. Nagy
Keyword(s):  
Protein Content ◽  
Starch Content ◽  
Sowing Date ◽  
Grain Protein Content ◽  
Water Supplies ◽  
Maize Hybrids ◽  
Growing Seasons ◽  
Sowing Dates ◽  
Significant Difference ◽  
Late Sowing

The yield, protein and starch content of Martonvásár maize hybrids belonging to different FAO groups were examined in experiments involving early, optimal and late sowing dates in two different years (drought — 2007, favourable water supplies — 2008) on a calcareous chernozem soil with loam texture at the Látókép Experimental Station of the Centre of Agricultural Sciences and Engineering, University of Debrecen.Sowing date had a significant effect on maize grain yield in the dry year. The grain yields of hybrids with longer growing periods were significantly higher than those with shorter growing periods in both years, but they reacted sensitively to the change in sowing date in the dry year. Due to the rainfall distribution in the growing season, sowing date did not modify the performance of the hybrids in the year with favourable water supplies. Sowing date had a significant effect on the grain protein content in the dry year, with significantly higher values after late sowing than after early or optimal sowing. Averaged over the sowing dates, the protein content of the FAO 200 hybrid was significantly higher in both years than that of hybrids in other FAO groups. In the dry year, the greatest difference in protein content could be observed between the early and late sowing dates for hybrids in all four FAO groups. A negative correlation was found between yield and protein content. Sowing date significantly increased the starch content of maize in the favourable year, with a significant difference between early and late sowing dates.In the dry year higher starch contents were recorded for all the hybrids and for all the sowing dates than in the favourable year. In the dry year, sowing date only caused a significant difference in the starch content in the case of FAO 200 sown at optimal and late sowing dates. In the favourable year, a significant difference was only obtained for the starch content of the FAO 400 hybrid sown at early and late sowing dates. Satisfactory quality can only be achieved if suitable genotypes are grown with appropriate technologies.

scholarly journals Concentrations and Loads of Dissolved and Particulate Organic Carbon in Urban Stormwater Runoff

Water ◽  
2020 ◽  
Vol 12 (4) ◽  
pp. 1031 ◽  
Author(s):  
Stefan Kalev ◽  
Gurpal S. Toor
Keyword(s):  
Organic Carbon ◽  
Stormwater Runoff ◽  
Light Availability ◽  
Rain Gauge ◽  
Urban Landscapes ◽  
Storm Events ◽  
Wet Season ◽  
The Difference ◽  
Urban Stormwater Runoff ◽  
High Concentrations

Urban landscapes are significant contributors of organic carbon (OC) in receiving waters, where elevated levels of OC limit the light availability, increase the transport of pollutants, and result in high costs of potable water treatment. Our objective in this study was to investigate the concentrations, fractions (dissolved and particulate), and loads of OC in a residential catchment (3.89 ha drainage area) located in Florida, United States. The outlet of the stormwater pipe draining the residential catchment was instrumented with an automated sampler, a flowmeter, and a rain gauge. The rainfall and runoff samples collected over 25 storm events during the 2016 wet season (June to September) were analyzed for dissolved organic carbon (DOC) and total organic carbon (TOC), with particulate OC (POC) calculated as the difference between TOC and DOC. Mean concentration of DOC was 2.3 ± 1.7 mg L−1 and POC was 0.3 ± 0.3 mg L−1 in the rainfall, whereas DOC was 10.5 ± 6.20 mg L−1 and POC was 2.00 ± 4.05 mg L−1 in the stormwater runoff. Concentrations of DOC were higher during the rising limb of the hydrograph in 15 out of 25 storm events, suggesting flushing of DOC, with an increase in the amount of runoff, from the landscape sources in the residential catchment. The estimated total export of OC during the 2016 wet season was 66.0 kg ha−1, of which DOC was 56.9 kg ha−1 (86.2% of TOC), and POC was 9.1 kg ha−1 (13.8% of TOC). High concentrations and loads of OC, especially DOC, in the stormwater runoff imply that residential catchments in urban watersheds are hot-spots of DOC influx to water bodies. Reducing DOC transport in the urban landscapes is complex and require identifying the origin of DOC and then using site-specific targeted approaches to mitigate DOC loss.

scholarly journals Effects of Iodine Agronomic Bio- fortification on selected Physiological Characteristics of Cassava in Calabar, Southeastern Nigeria

2018 ◽  
Vol 5 (4) ◽  
pp. 116
Author(s):  
Ansa, J. E. O ◽  
Binang, W. B.
Keyword(s):  
Protein Content ◽  
Field Experiments ◽  
Starch Content ◽  
Block Design ◽  
Iodine Content ◽  
Physiological Data ◽  
Southeastern Nigeria ◽  
Time Of Application ◽  
Tuber Protein ◽  
Cassava Varieties

Field experiments were conducted between November 2011 and May 2014 at the Crop Science Teaching and Research Farm of the University of Calabar, (Southeastern rainforest agro-ecological zone of Nigeria) to determine the effectiveness of Iodine agronomic fortification of cassava. The field experiment was a 2x3x4 factorial experiment arranged in randomized complete block design replicated three times, conducted using two cassava varieties,( TME 419 and TMS 30555); four iodine rates( 0, 2.5, 5.0 and 10.0) kg/ha KI; applied at 8, 10 and 12 WAP. Physiological data were obtained by determination of Iodine content [in cassava tuber]; tuber cyanide content (HCN); Carbohydrate content of tuber; starch content of tuber and tuber protein contents. Iodine absorption and retention in cassava tuber flesh was significantly positively correlated with Iodine doses at the times of application (p0.05 and 0.01). TME 419 retained more Iodine in tissues than TMS 30555 and recorded highest correlation co-efficient at 10WAP. Iodine doses and time of application did not significantly control (P≥0.05) contents of cyanide, carbohydrate and starch in cassava tubers. Protein content was significantly varied in cassava varieties and rate and time of Iodine application influenced tuber protein content. TME 419 produced more tuber protein, Iodine doses of 2.5kg/ha KI and 0kg/ha KI had higher protein content than 5kg and 10kg/ha KI. Application at 8WAP and 10WAP were not significantly different. For favourable physiological cassava characteristics, 2.5kg/ha KI is recommended applied 10 weeks after planting (WAP).

EFFECTS OF VARIETY AND ENVIRONMENT ON THE STARCH CONTENT OF WHEAT AND BARLEY

1943 ◽  
Vol 21c (10) ◽  
pp. 307-321 ◽  
Author(s):  
A. G. McCalla ◽  
W. G. Corns
Keyword(s):  
Protein Content ◽  
Environmental Conditions ◽  
Starch Content ◽  
Correlation Coefficients ◽  
Prairie Soils ◽  
Wide Range ◽  
Significant Regression

Starch content of six varieties each of wheat and barley grown under a wide range of environmental conditions was determined polarimetrically. Environment had a greater effect on starch content than did variety, but both effects were highly significant. Correlation coefficients as high as −.970 were obtained between starch and protein content, and for every variety coefficients were highly significant. Regression of starch on protein yielded coefficients numerically well above −1.0 for both wheat and barley.Barley yielded 16% more starch per acre, on the average, than did wheat. Yields of starch per acre were highest in grain grown on parkland soils, and lowest in that on prairie soils.

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